Refinement Database

Database on Refinement of Housing, Husbandry, Care, and Use of Animals in Research

This database, created in 2000, is updated every four months with newly published scientific articles, books, and other publications related to improving or safeguarding the welfare of animals used in research.

Tips for using the database:

  • This landing page displays all of the publications in the database.
  • Use the drop-down menus to filter these publications by Animal Type, Setting, and/or Topic.
  • Clicking on a parent category (e.g., Rodent) will include publications relating to all the items in that category (e.g., Chinchilla, Gerbil, Guinea Pig, etc.).
  • You may also add a keyword to further narrow your search.
  • Please note that at this time, only publications dated 2010 or later (with some exceptions) can be filtered by Animal Type and Topic, and only publications dated 2020 or later (with some exceptions) can be filtered by Setting. Most publications older than 2010 can only be searched by keyword. 
Fares, R. P., Belmeguenai, A., Sanchez, P.E. et al. 2013. Standardized environmental enrichment supports enhanced brain plasticity in healthy rats and prevents cognitive impairment in epileptic rats. PLOS ONE 8(1): e53888.

Environmental enrichment of laboratory animals influences brain plasticity, stimulates neurogenesis, increases neurotrophic factor expression, and protects against the effects of brain insult. However, these positive effects are not constantly observed, probably because standardized procedures of...

Azar, T. A., Sharp, J. L., Lawson, D. M. 2012. Effects of cage enrichment on heart rate, blood pressure, and activity of female Sprague-Dawley and spontaneously hypertensive rats at rest and after acute challenges. JAALAS 51(3), 339-344.

Here we sought to determine whether a nonsocial cage enrichment program, identical to one we previously used with male rats, was effective in reducing heart rate or systolic blood pressure (SBP) in female Sprague-Dawley rats...

Olivo, D. 2012. The benefits of adding a little color to a monkey's environment. Enrichment Record 10, 7.

Imagine if your everyday world was boring, blah and completely sterile looking with limited amounts of color. Unimaginable, right? Here at Legacy Schering Plough/Merck, we thought the same about our nonhuman primates who look at...

Froberg-Fejko, K. M., Lecker, J. L. 2012. Going back to nature: The benefits of wood enrichment. Lab Animal 41(11), 345-347.

Environmental enrichment can be defined as altering the living environment of captive animals in order to provide them with opportunities to express more of their natural behavioral repertoire. The challenge of providing effective enrichment in...

Maertens, L., Buijs, S., Davoust, C. 2012. Gnawing blocks as cage enrichment and dietary supplement for does and fatteners: Intake, performance and behaviour. World Rabbit Science 21(S1), 185-192.

The aim of this study was to evaluate different experimental gnawing blocks as cage enrichment in rabbits. One hundred and five pregnant rabbit does housed in conventional wire cages were distributed according to their parity...

Luchins, K. R., Baker, K. C., Gilbert, M. H. et al. 2011. Manzanita wood: A sanitizable enrichment option for nonhuman primates. JAALAS 50(6), 884-887.

Wooden objects are often used as nonhuman primate enrichment to provide variety and novelty, promote exploratory behavior, and supply an outlet for curiosity. However, concerns have been raised regarding the ability to sanitize wood by...

Buijs, S., Maertens, L., Tuyttens, F. A. M. et al. 2011. Glucocorticoid metabolites in rabbit faeces - Influence of environmental enrichment and cage size. Physiology & Behavior 104(3), 469-473.

The concentration of glucocorticoid metabolites (GCM) in rabbit faeces has been suggested as a non-invasive indicator of stress. In the present study, GCM concentrations were measured in faeces of fattening rabbits kept in groups of...

Poggiagliolmi, S., Crowell-Davis, S. L., Alworth, L. C. et al. 2011. Environmental enrichment of New Zealand white rabbits living in laboratory cages. Journal of Veterinary Behavior 6(6), 343-350.

The primary goal of environmental enrichment should be the avoidance of abnormal behaviors in laboratory animals such as rodents, lagomorphs, dogs, cats, and nonhuman primates. A total of 13 male single-housed New Zealand White rabbits...

Abou-Ismail, U. A., Mahboub, H. D. 2011. The effects of enriching laboratory cages using various physical structures on multiple measures of welfare in singly-housed rats. Laboratory Animals 45(3), 145-153.

The single housing of laboratory rats may be recommended in some situations such as hypothesis-driven or test-specific studies, during electroencephalogram recording of phases of sleep and after surgical procedures. However, as single housing of laboratory...

Akiyama, K., Sutoo, D. 2011. Effect of different frequencies of music on blood pressure regulation in spontaneously hypertensive rats. Neuroscience Letters 487(1), 58-60.

The effect of different frequencies of music on brain function was investigated through measurement of blood pressure in spontaneously hypertensive rats (SHR). Previous studies indicated that exposure to Mozart's music (K. 205) leads to increased...

Abou-Ismail, U. A. 2011. Are the effects of enrichment due to the presence of multiple items or a particular item in the cages of laboratory rat? Applied Animal Behaviour Science 134(1-2), 72-82.

Although the effects of environmental enrichment on laboratory rodents have been extensively described, it is not yet known whether these effects were simply due to the presence of multiple items in the cage or due...

Wood, L. L., Boyd, A. M., Rose, R. et al. 2011. Implementation of an enrichment rack for singly housed male nonhuman primates. American Association for Laboratory Animal Science [AALAS] Meeting Official Program, 732 (Abstract #PS54).

The racks provide four different levels of horizontal bars where manipulanda can be hung. .. The racks are positioned in front of a 4-caged housing system. .. The enrichment racks have produced an increase in...

Witt, S. L., Plews, C. A., Ruppert, G. et al. 2011. Nylon cylinder: Safe and cost-effective chewable rat enrichment. American Association for Laboratory Animal Science [AALAS] Meeting Official Program, 782 (Abstract #P174).

Offering enrichment to stimulate chewing behavior in rats has been found to promote psychologic and physiologic wellbeing. While there are many commercially produced nylon products available for use as chewable enrichment, these items are costly...

Neubauer, T., Buckmaster, C. 2011. Decline in aggression in cotton rats through enrichment. Tech Talk [The Newsletter for Laboratory Animal Science Technicians] 16(4), 2-3.

The tubes provide shelter and nesting material to the rats, allowing them to exhibit species-specific behaviors. The change in the animals' behavior has been overwhelming. The rats are much less aggressive; in one year, fight...

Krohn, T. C., Salling, B., Kornerup Hansen, A. 2011. How do rats respond to playing radio in the animal facility? Laboratory Animals 45(3), 141-144.

In the animal facility, a range of different sounds are present. On the one hand, rats and humans will regard sound and noise differently even within the audible range, but on the other hand mice...

Buck, C., Pittman, P., Coburn, A. et al. 2011. Primate foraging ice blocks: Cool treats and interactive eats. Tech Talk [The Newsletter for Laboratory Animal Science Technicians] 16(3), 2.

The [ice] blocks provide a stimulating foraging experience for the NHPs. The blocks last up to an hour fully melting; however, most NHPs have them broken apart and are eating them within 15 minutes. Some...

Brydges, N. M., Leach, M., Nicol, K. et al. 2011. Environmental enrichment induces optimistic cognitive bias in rats. Animal Behaviour 81(1), 169-175.

People's affective or emotional state can alter their cognitive processing, biasing interpretation of ambiguous stimuli. Those in a more positive state interpret such stimuli in a more optimistic manner than those in a negative state...

Research Department, RSPCA. 2011. Rabbits: Good Practice for Housing and Care (3rd edition).

This report describes what rabbits need in terms of social housing, enclosure size and type, and environmental enrichment. It also describes potential husbandry-related welfare problems and how to resolve them.

Abou-Ismail, U. A., Burman, O. H. P., Nicol, C. J. et al. 2010. The effects of enhancing cage complexity on the behaviour and welfare of laboratory rats. Behavioural Processes 85(2), 172-180.

This experiment was carried out to investigate the long-term effects of enhancing cage complexity on behavioural measures of welfare in laboratory rats. We housed 72 rats in groups of four in either ‘enriched’ or ‘unenriched’...

Waitt, C. D., Bushmitz, M., Honess, P. E. 2010. Designing environments for aged primates. Laboratory Primate Newsletter, 49(3), 5-9.

In order to prevent physical and psychological deterioration in older animals, it is important to apply the same principles of environmental enrichment and housing as are applied to younger animals. As we have discussed above...

Lozano, A., West, A., Leland, S. et al. 2010. Preventing boredom in NHPs using fleece fabric and food treats. Tech Talk [The Newsletter for Laboratory Animal Science Technicians] 15(5), page numbers missing.

Recently, I devised yet another way to use this fleece material to enhance the environments of our animals. To this end, I sought out a way to present food enrichment to our animals so that...

Williams-Fritze, M. J., Altieri, J. A., Clough, C. et al. 2010. Modification of a dog cage for use as an exercise unit for rabbits. American Association for Laboratory Animal Science [AALAS] Meeting Official Program, 703 (Abstract #P70).

The Guide for the Care and Use of Animals and the USDA Animal Welfare Regulations (AWR) outline minimum space requirements for laboratory animals, including rabbits. These documents encourage housing of animals in enclosures that allow...

Turner, P. V., Ovari, J., Pinelli, C. et al. 2010. Long-term effects of housing and enrichment on affective behavior and responsiveness of Sprague-Dawley rats. American Association for Laboratory Animal Science [AALAS] Meeting Official Program, 658-659 (Abstract #PS12).

Most rodent studies evaluate different caging paradigms over short periods of time, which may not be realistic for typical colony settings. Inappropriate housing may lead to boredom, aggression, stereotypies, and altered metabolism, which in turn...

Newman, A. 2010. A simple improvement of rodent tunnels for environmental enrichment. Animal Technology and Welfare 9, 57-58.

We found commercially available rodent tunnels are too small in diameter when the rat reaches a size

Mikkelsen, L. F., Sørensen, D. B., Krohn, T. et al. 2010. Clinical pathology and cardiovascular parameters are not influenced by housing rats under increased environmental complexity. Animal Welfare 19(4), 449-460.

Since the release of the revised Appendix A from the Council of Europe for housing of laboratory animals there have been claims that laboratory animals should be housed under more complex conditions; known popularly as...